Endoscopic surgery is a minimally invasive surgical procedure that is used to analyze the interior of a body cavity or interior surfaces of an organ by inserting a tubular member into the body cavity through a minimal incision. A conventional endoscope (sometimes referred to herein simply as a “scope”) is generally an instrument with an image sensor for visualizing the interior of a body cavity. A wide range of applications have been developed for the general field of endoscopes including, but not necessarily limited to; arthroscope, angioscope, bronchoscope, choledochoscope, colonoscope, cytoscope, duodenoscope, enteroscope, esophagogastro-duodenoscope (gastroscope), laparoscope, laryngoscope, nasopharyngo-neproscope, sigmoidoscope, thoracoscope, and utererscope (hereinafter referred to generally as “endoscope”). The advantages of endoscopic surgery include smaller surgical incisions and less soft tissue damage. As a result, there is significantly less discomfort and pain for the patient as well as a decrease in recovery time.
As part of forming an image of the surgical site, the endoscope includes an image sensor. Endoscopes may also incorporate a light source and one or more tubular members for observation or operation within the body, such as a working channel for passing diagnostic, monitoring, treatment, or surgical tools through the endoscope. An endoscopic system typically includes an image sensor (e.g. a camera) coupled to a camera control unit (CCU). The CCU captures and processes video signals from the image sensor for display on a monitor, as well as for transfer to existing recording and printing devices. The image sensor typically communicates with the CCU by way of a cable.
Image sensor processing circuitry is configured for either a Complimentary Metal Oxide Semiconductor (CMOS) image sensor or a Charge Coupled Device (CCD) image sensor. CCU circuitry is typically hard wired for the specific type of sensor it was designed to work with. It is not possible with commercial systems to interchange a CCD sensor into a CCU designed to work with a CMOS sensor or to interchange a CMOS sensor into a CCU designed to work with a CCD sensor. A CCD sensor output is an analog signal whereas a CMOS sensor output is typically a digital signal. The different types of sensors require considerably different support and interface circuitry. The additional complexity of developing a CCU that would handle both types of sensors has prevented this from becoming commercially feasible.